Automatic document-feeding apparatus

ABSTRACT

An automatic document-feeding apparatus is disclosed. The automatic document-feeding apparatus comprises means for picking up and transporting document sheets, means for separating document sheets into a sequence of transportation, and means for pressing document sheets. The means for picking up and transporting document sheets contact and transport document sheets and the means for separating document sheets comprise an incline plane used to receive and support the document sheet being transported from the means for picking up and transporting document sheets. The means for pressing document sheets press the document sheets to keep the document sheets and the incline plane in tight contact.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to an automatic document-feedingapparatus, and more particularly to an automatic document-feedingapparatus with superior capability of document pagination.

[0003] 2. Description of the Related Art

[0004] It is publicly known to use a document feeding apparatusso-called as an automatic document feeder (ADF) in order to supplyautomatically a document to a document reading portion in an imageforming apparatus. The automatic document feeder (ADF) is a usefuldevice for documenting image input system such as image scanner. In theapplication of the so-called “Paper-Feed” image input device, theautomatic document feeder functions to transport page by page documentscontaining image data, into the scanning area of the image input device.

[0005]FIG. 1 shows the basic structure of a conventional automaticdocument feeder. As shown in the figure, the automatic document feedercomprises a pagination roller 102, a pickup roller 104 and a retard pad108. The retard pad 108 is pressed against the pagination roller 102 bya pressure spring 106. A stack of documents 110 are mounted on bottom ofthe pickup roller 104.

[0006] Ideally, when the pickup roller 104 starts to rotate, a document110 at the top of the stack of the documents is fetched by the pickuproller 104 to the retard pad 108 and all documents other than the one atthe top of the stack are stopped since only the one at the top of thestack can contact the pickup roller 104. The document at the top of thestack is then transported to the retard pad 108 and under the paginationroller 102 by the pickup roller 104.

[0007] However, the conventional automatic document feeder describedabove indeed presents a problem which would harm the function of animage scanner. The problem is that the continuous fed documents are notseparated well when the pickup roller 104 picks up and sends more thanone document sheet once. That is, more than two document sheets aretransported to the retard pad 108 and under the pagination roller 102usually. The excess fed document sheets undoubtedly would impede thenormal operation the whole machine since the excess fed document sheetscould hinder the feeding of the following document sheets or jam in theautomatic document feeder. Therefore, it is desirable to provide anautomatic document-feeding apparatus with superior capability ofdocument pagination to overcome the problem of the prior art.

SUMMARY OF THE INVENTION

[0008] It is therefore an object of the invention to provide anautomatic document-feeding apparatus with superior capability ofdocument pagination.

[0009] It is another object of this invention to provide a reliableautomatic document-feeding apparatus.

[0010] To achieve these objects, and in accordance with the purpose ofthe invention, the invention provide an automatic document-feedingapparatus with superior capability of document pagination. In oneembodiment of this invention, the apparatus comprises means for pickingup and transporting document sheets, means for separating documentsheets into a sequence of transportation, and means for pressingdocument sheets. The means for picking up and transporting documentsheets contact and transport document sheets and the means forseparating document sheets comprise an incline plane used to receive andsupport the document sheet being transported from the means for pickingup and transporting document sheets. The means for pressing documentsheets press the document sheets to keep the document sheets and theincline plane in tight contact.

[0011] In another embodiment of this invention, the automaticdocument-feeding apparatus of this invention comprises means for pickingup document sheets, means for separating document sheets into a sequenceof transportation, means for pressing document sheets, and means fortransporting document sheets. The means for picking up document sheetscontact and pick up document sheets and the means for separatingdocument sheets comprise an incline plane used to receive and supportthe document sheet being transported from the means for picking updocument sheets. The means for pressing document sheets press thedocument sheets to keep the document sheets and the incline plane intight contact and the means for transporting document sheets receive andtransport the document sheets being transported from the means forseparating document sheets.

[0012] It is to be understood that both the foregoing generaldescription and the following detailed description are exemplary andexplanatory only and are not restrictive of the invention, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The foregoing aspects and many of the attendant advantages ofthis invention will become more readily appreciated as the same becomesbetter understood by reference to the following detailed description,when taken in conjunction with the accompanying drawings, wherein:

[0014]FIG. 1 shows the basic structure of a conventional automaticdocument feeder; and

[0015]FIG. 2 shows an automatic document-feeding apparatus of thisinvention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0016] It is to be understood and appreciated that the apparatusdescribed below do not cover a complete system. The present inventioncan be practiced in conjunction with various hardware that are used inthe art, and only so much of the commonly practiced components and stepsare included herein as are necessary to provide an understanding of thepresent invention.

[0017] The present invention will be described in detail with referenceto the accompanying drawings. It should be noted that the drawings arein greatly simplified form.

[0018] Referring to FIG. 2, an automatic document-feeding apparatus 200of this invention is shown. In one embodiment of this invention, theautomatic document-feeding apparatus 200 comprises means for picking upand transporting document sheets, means for separating document sheetsinto a sequence of transportation and means for pressing document sheetscomprising a pressing plate 212. The means for picking up andtransporting document sheets comprise rollers 202 and 204 as well as atleast one motor (not shown) driving the rollers 202 and 204. The roller204 comprising a rubber roller is used to contact, pick up and drive thetop sheet of a stack of document sheets 210. The roller 202 comprising arubber roller is used to transport the document sheet from the roller204 to the scanning area of an image scanner. The roller 202 and 204could be drove by a single motor or two motors individually and rollsynchronously. The means for separating document sheets into a sequenceof transportation comprises a supporting pad 208 as well as a pluralityof spring 206 pushing the supporting pad 208 against to the roller 202.The pressing plate 212 provides the document sheets 210 with a downwardpressing force so that the document sheets 210 can be pressed and thefront edges of the document sheets 210 can keep a tight contact with thesupporting pad 208. The pressing plate 212 can be pivoted on a pivot 205which is also the pivot of the roller 204. The pressing plate 212 canalso be mounted somewhere else. The supporting pad 208 preferablycomprises an incline plane 208 a and a cave surface 208 b. The inclineplane 208 a provides the document sheets 210 with an upward pushingforce and a separating force so that the top one of the document sheets210 can keep a tight contact with the pressing plate 212 and thedocument sheets 210 can be separated into a sequence of transportationwhile the roller 204 rolls. The cave surface 208 b provides the documentsheet 210 being transported with a support so that the document sheet210 can contact with the roller 202 tightly. The cave surface 208 bcontacts the roller 202 while no document sheet is inserted therebetweenso as to provide the document sheet 210 with a friction force. Thesprings 206 support and push the supporting pad 208.

[0019] Other embodiments of the invention will appear to those skilledin the art from consideration of the specification and practice of theinvention disclosed herein. It is intended that the specification andexamples to be considered as exemplary only, with a true scope andspirit of the invention being indicated by the following claims.

What is claim is:
 1. An automatic document-feeding apparatus, said apparatus comprising: means for picking up and transporting document sheets, said means for picking up and transporting document sheets contact and transport document sheets; means for separating document sheets into a sequence of transportation, said means for separating document sheets comprise an incline plane used to receive and support the document sheet being transported from said means for picking up and transporting document sheets; and means for pressing document sheets, said means for pressing document sheets press the document sheets to keep the document sheets and said incline plane in tight contact.
 2. The apparatus according to claim 1, wherein said means for picking up and transporting document sheets comprise a roller for picking up document sheets and a roller for transporting document sheets, said roller for transporting document sheets receives document sheets from said roller for picking up document sheets.
 3. The apparatus according to claim 2, wherein said roller for picking up document sheets and said roller for transporting document sheets are drove by a motor.
 4. The apparatus according to claim 2, wherein said roller for picking up document sheets and said roller for transporting document sheets are drove by two motors individually.
 5. The apparatus according to claim 2, wherein said rollers comprise rubber rollers.
 6. The apparatus according to claim 1, wherein said means for pressing document sheets comprise a pressing plate
 7. An automatic document-feeding apparatus, said apparatus comprising: means for picking up document sheets, said means for picking up document sheets contact and pick up document sheets; means for separating document sheets into a sequence of transportation, said means for separating document sheets comprise an incline plane used to receive and support the document sheet being transported from said means for picking up document sheets; means for pressing document sheets, said means for pressing document sheets press the document sheets to keep the document sheets and said incline plane in tight contact; and means for transporting document sheets, said means for transporting document sheets receive and transport the document sheets being transported from said means for separating document sheets.
 8. The apparatus according to claim 7, wherein said means for picking up document sheets comprise a roller.
 9. The apparatus according to claim 7, wherein said means for separating document sheets comprises a supporting pad and springs pushing said supporting pad against said means for pressing document sheets.
 10. The apparatus according to claim 7, wherein said means for pressing document sheets comprise a pressing plate.
 11. The apparatus according to claim 7, wherein said means for transporting document sheets comprise a roller.
 12. An automatic document-feeding apparatus, said apparatus comprising: a first roller, said first roller contacts and picks up document sheets; a supporting pad, said supporting pad comprises an incline plane used to receive and support the document sheet being transported from said first roller and a cave surface; means for pressing document sheets, said means for pressing document sheets press the document sheets to keep the document sheets and said incline plane in tight contact; and a second roller contacting said cave surface, said second roller receives and transports the document sheets being transported from said incline plane.
 13. The apparatus according to claim 12, wherein said first roller comprises a rubber roller.
 14. The apparatus according to claim 12, wherein said supporting pad comprises a rubber pad and springs pushing said rubber pad against said second roller and said means for pressing document sheets.
 15. The apparatus according to claim 12, wherein said means for pressing document sheets comprise a pressing plate.
 16. The apparatus according to claim 12, wherein said second roller comprises a rubber roller.
 17. The apparatus according to claim 12, wherein said first and second rollers are drove by a single motor.
 18. The apparatus according to claim 12, wherein said first and second rollers are drove by two motors individually. 